Steam trap



May 1, 192a 1,667,935

F. LE C. HUTCHINSON STEAM TRAP Original Filed March 14. 1925 A TTORNEYS Patented May 1, 1928.

UNITED STATES.

FRANK LE CLAIR HUTCHINSON, 0F WAUWATQSA, WISCONSIN, ASSlZGNOR TO CON- 1,667,935 PATENT OFFICE.

SOLIDATED STEAM SPECIALTY COMPANY, A CORPORATION OF DELAWARE.

STEAM TRAP.

Application filed March 14, 1925, Serial No. 15,668. Renewed November 23, 1 927.

This invention relates to improvements in steam traps, and more particularly to a steam trap adapted to be connected. to the return pipe in a steam or vapor heating systerm.

In heating systems employed in buildings, utilizing steam under ressure, it is customary tocontrol the a mission of steam to the radiator and to provide an outlet pi e to return Water of condensation back to t e boiler. In order to make the system eonducive of the best results and to provide for its maximum efficiency, it is necessary to prevent the passage of any of the live steam back through the return pipe with the water of condensation. It is. also necessary in systems of this character to provide means whereby air which may be trapped in the radiator can escape, so that the air willnot act to prevent the entrance of steam into the radiator.

Hence, it is the principal object of the present invention to provide a device adapted to be connected to the return pipe and constructed to permit the passage of water of condensation therethrough and also any air trapped in the radiator.

A further object of the invention is to provide a thermally controlled steam trap con structed so that the radiator itself is utilized as a chamber for the thermal or expansion member.

A further object of the invention is to provide asteam trap which is readily attached to a steam radiator by being threaded into the discharge end thereof.

A further object of the invention is to provide a steam trap which is of very simple construction, is inexpensive to manufacture and install, is strong and durable, is efficient in operation, and is well adapted for the purposes described.

With the above and other objects in view,

the invention consists of the improved steam trap, and its parts and combinations as set forth in the claims, and all equivalents thereof.

In the accompanying drawings in which the same reference characters indicate the same parts in all of the views:

Fig. 1 is a fragmentary view of the drain end portion of a radiator having the improved steam trap installed therein, part being broken away and shown in section;

Fig.2 is a longitudinal sectional view of the steam trap on a larger-scale; and

Fig. 3 is a sectional view taken on line 33 of Fig. 2.

Referring now more particularly tothe drawing it will be seen that the numeral 5 indicates a tubular nipple member threaded as at 6 and having a shouldered outer end portion 7. The inner end portion of the member 5 is reduced as at 8 and is formed with an opening or channel 9 communicating with the interior of said member. A transverse opening or valve seat 10 leads to the channel 9.

A bi metallic strip 11 o'f U-formation 'is secured at one end portion to the reduced end portion 8 of the tubular nipple member and the free end portion of said strip carries a rounded valve member 12 said valve member 12 being in juxtaposition to the valve opening or seat 10. The bimetal strip or thermostatic member 11 is formed preferably of an outer strip of brass or copper and an inner strip .of steel or a similar metal, having a different coefficient of expansion,

and hence the free end portion of said.

i of the nipple member 5 and thereby connects the same to the elbow member The thread ed end portion 6 of the member 5 is screwed into the internally threaded bore 16 atthe discharge end of radiator 17 so that the reduced end portion 8 and the thermostatic strip 11 are entirely within the confines of the radiator.

It will be observed that the elbow member 1 1 is formed with a hushed portion 18 provided with a bore in alinement with the interiorof the nipple member, the bore being normally closed by a threaded plug 19. By removing the plug the device andopenings can be cleared of dirt and sediment, if

necessary.

The operation of the steam trap is as follows: WVhen the radiator is filled with live steam the heat therefrom will influence the thermostatic strip to the extent that it will be bent so that the valve member will tightly seat in the valve opening 10 and close the same, thus preventing the escape of the live steam. However as soon as an appreciable amount of water of condensation has collected within the radiator its cooling effect will be felt by the thermostatic member with the result that the outer end will automatically llex outwardly to lift the valve member 12 from its seat and open the passage-way 9. The water can then drain out of the radiator through the elbow member and drain pipe. The result is the same when air collects in the radiator. The temperature thereof will cause a movement of the strip ll to open the valve and allow the escape of the air. As soon as sullicient live steam again enters the radiator, the valve will be automatically closed to prevent the escape thereof.

It will thus be seen that in the improved steam trap the necessity of a separate chamber for the valve and valve operating mechanism is eliminated as said mechanism and valve utilize the interior of the radiator for a chamber. This materially increases the simplicity of the device as to manufacture and installation and permits the provision of an inexpensive and ellicient steam trap. Also. from the foregoing description it will be seen that the improved steam trap is of very simple and novel construction, and is well adapted for the purpose set forth.

What 1 claim as my invention is:

1. The combination with a radiator and a drain pipe, of a tubular member connected to the drain pipe and extending into the radiator, and a thermally controlled valve integral with said tubular member and with in the radiator for closing the opening of said tubular member.

2. The combination with a fluid heated chamber having a drain member of a tubular member in connection with said drain member and extending into the heating; chamber. and thermally controlled means carried by said tubular member and confined only within said heating chamber for opening or closing the inner opening of said tubular member.

3. The combination with a fluid heated chamber having a drain member, of a tubular member in connection with said drain member and extending into said heating, chamber, said tubular member having an inner valve opening, and a bi-metallie strip carried by the inner end portion of the tubular member within the chamber and formed with a valve portion for seating in said valve opening.

*l. A steam trap tor a heating chamber provided with a discharge opening, comprising a tubular member insertable in said discharge opening and having an inner opening. and a thermally controlled valve member associated with said tubular member and confined within said heating chamber for controlling said inner openin A steam trap for a l .lll'iilg chamber provided vith a discharge opening, comprising a tubular member arranged to be threaded into said discharge opening and having; an inner opening. and a thermally controlled valve member carried by the inner end port ion of the tubular member and confined within said heating chamber for controlling said inner opening.

(5. A steam trap for connection with a radiator and a radiator drain pipe. com prising an elbow member. a tubular member. a union nut rcvolubly connecting the tubular member to the elbow member, and a bimetallic member carried by the free end portion of the tubular member. said hi-metallie member carrying a valve member to control the inner opening; ol' the tubular member.

7. In combination, a lluid heated radiator having" an internally threaded discharge opening, a tubular member having one end portion threaded into said discharge opening. a U-shaped iii-metallic strip secured at one end to the inner end portion of said tubular member and entirely within the ra diator a valve member carried by the free end portion of said strip for controlling the inner ()[itlllllhf ol said tubular member. a discharge pipe. and means for connecting the outer end portion of the tubular member to the discharge pipe.

In testimony whereof. I allix my signature.

FRANK LE CLAIR HUTGI-IINSON.

till 

